a major step in the long legal journey involving suspect dzhokhar tsarnaev. >> the 19-year-old charged with a federal crime, which brings the ultimate punishment. abc's marci gonzalez joining us this morning from boston with more. marci. >> reporter: good morning, john and diana. we learned at his bedside arraignment, the suspect said just one word. when asked if he could afford an attorney, he replied no. among the charges, 19-year-old suspect, dzhokhar tsarnaev faces one count of using a weapon of mass destruction. which carries a potential maximum sentence of death. we've learned despite the injury to his neck, he is cooperating with investigators, writing his answers to at least some of their questions. sources tell abc news, among the details he has provided is that he and his brother learned how to make bombs from the internet. >> it was his brother, the primary motivating force for him to become radicalized. why did they end up doing what they did on that day? >> reporter: much of the investigation is still focused on his deceased 26-year-old brother tamerlan. examining his life